Flat battery help needed

[Maffoo]

Today i put the last parts on my CB250 rebuild, went to start it & the damn battery is dead... not tooootally dead, but dead enough to nopt turn the bike over...
my question is, whats the best way to charge it? its not possible to jump start them unless its off another bike eh? I have tried crash starting it too, no luck..
is a battery charger the only way?
it seems a fairly good quality battery so i dont really want to have to buy another one... how well do bike batteries last once they have been flattened?
any advice would be great, cheers
matty

[Ixion]

You can jump start it from a car battery. A battery is a battery is a battery. Best NOT to have the car engine running though.

Just connect in the usual way, +ve to +ve , -ve to -ve etc. Use good quality jump leads ahlf the time people use the cheap ones and they have so much resistance you might as well not have another battery.

Then press the button. Best not to remove the jumpers while running , though sometimes needs must. If possible run it for a few minutes , turn off, disconnect , and it hopefully will restart on its own battery.

[surfer]

Way up the options and consider how long have you spent on this project? How much money has been spent? Will a few hours really make that much difference to you?

You might want to consider doing the job properly. The best way is have a fully charged battery; either buy or borrow a battery charger and leave it on over night on a trickle charge.

Failing this you might want to try jump starting your bike; ok if it is a bit flat.

If you are in a real bind you can use a battery off a car to get you going so long as the car is NOT running. This is very important as the load is too big and you will do damage. Also as the battery is left in situ in the bike there is also the chance of you touching live wires and doing some damage as you try and navigate your way in to fiddly places.

Not sure how long a battery will last. This depends on what you are going to do with it over its lifetime. I had heard that a battery may need replacing every to or thee years but others on this site might know better. (My batteries seem to last a bit longer than this).

Hope this helps.

[Maffoo]

ive spent 6 months on the rebuild, the thing is im back at tech tomorrow & ive just waited a week to get my seat out of a locked garage so im really quite impatient right now

i might try jump-starting it. I have good quality leads with the little resistor box thing on them. it was last running about three weeks ago & it has brand new fuel in it, so im hoping it wont take long to kick. my main concern was frying the battery while jump-starting it.
thanks for your advice, ill let you know how it goes (& watch for the "i finally finshed my bikes!!") thread coming up soon

[Maffoo]

i got it going off my car
its now idling happily on the driveway, & ill leave it for a while doing just that
cheers guys

[surfer]

You run the risk of overheating if you leave it idling long enough (if it is air cooled).

Best to take it for a good run. But don't use the indicators or lights so go now. These will drain the charge from your battery and you really want to top it up.

Enjoy

[Maffoo]

yeah i let it run for not too long, but when i turned it off it wont start again, i think the battery is rooted
i cant ride it, its not road-legal

[peasea]

yeah i let it run for not too long, but when i turned it off it wont start again, i think the battery is rooted
i cant ride it, its not road-legal

In my (30+ yrs) experience, the best way to re-charge a dead flat battery is slowly. A trickle charger isn't that expensive and always good to have around the workshop. If you're handy with the spanners and will look at other projects in the future then tooling up is important, a trickle-charger will be used again and again. As for your comment "I'm a bit impatient", don't be, it's easy to say and so hard to do, but really, one more night (which is all most trickle charges take) ain't gonna make that much difference. If a trickle charge hasn't got you going by the dawn parade, biff the battery.

[Ixion]

Bike at idling will take a long time to recharge the battery , maybe never. Either a longish fast ride (at least an hour) or a trickle charger.

[HungusMaximist]

Funny about batteries, I've bumped into the same problem as yourself a few weeks ago.

It's definitely wise to charge your battery with a battery charger and it should cost you no more than 40 bucks for a basic manual charger (which you have to switch off when it's fully charged) or little extra for those automatic trickle chargers.

Also check the water levels inside each cell, if it's below the 'low' limit line top it up with some water. Recommended that you use distilled if you can, but Auckland tap water is fine (my experience anyway as the water is resonably 'soft' in terms of minerals as such).

If you need to borrow a battery charger to charge up your battery properly give me a PM.

[Bob]

Get yourself an Optimate III charger.

Review here

Being able to fit a lead which can be permanently attached to the bike, making charging a doddle is worth the money on it's own!

[Max Preload]

Repco & Supercheap have charge & maintain style 12V chargers for significantly less than bike dealers will charge. I got a 800mA one (size of a small mains power pack like a cell charger) for a bike I didn't ride much, cut the alligator clips off and soldered a plug on the end (like this). Then I put in a flush mount fused charging point socket (like this) through the plastic side panel and simply plugged the bike in all the time it was in the garage.

[merv]

As another alternative I use the Projecta On-Board type 1600ma which I commented on before here http://www.kiwibiker.co.nz/forums/sh...ad.php?t=34508 only thing is now the price is up at K Mart and its Repco that's having a sale on Projecta so just shop around, but at the price they are still a better deal than the so-called bike chargers. The advantage with this model is you screw it to the wall near your bike and it comes with the short connection ready to bolt on to your bike battery i.e. leave it on the bike, and then you just plug in when you park the bike up.

We have 5 bikes on them seeing we are weekend only riders and don't use all the bikes every time either so they sit a while.

My 4x4 is only used when its needed too and its on a Projecta 2700ma charger.

Only buy the type labelled "charge and maintain" as mentioned above because you don't want your battery overcharged and fried dry.

[Max Preload]

Trouble with the onboard is that it's onboard... you have to find somewhere to install it, space that might well be better utilised for storing other things.

Mine was a "Projecta" too. I had this one I now have a bigger (5400mA) one which does the boat batteries quickly and easily too.

[merv]

No I mount the "on-board" on the wall, all that goes on the bike is the connection leads on the battery with the small plug and then it comes with a nice long lead to go from the wall unit to the plug. The same model can be actually mounted on-board boats and things like that but we don't need to on the bike you'd just be carrying useless weight.